The generic class of materials of .alpha.-olefin/vinyl or vinylidene monomer substantially random interpolymers, including materials such as substantially random (.alpha.-olefin/vinyl aromatic monomer interpolymers, and their preparation, are known in the art, such as described in U.S. Pat. No. 5,703,187 (EP416,815 A2), and in U.S. Pat. No. 5,872,201 the entire contents of which are incorporated herein by reference.
These materials offer a wide range of material structures and properties that make them useful for varied applications. Examples of useful applications for these substantially random interpolymers include their use as asphalt modifiers or compatibilizers for blends of polyethylene and polystyrene, as described in U.S. Pat. No. 5,460,818. Also, materials containing .alpha.-olefin/vinyl or vinylidene substantially random interpolymers display good elastic properties and energy dissipation capacities, and thus are also useful in adhesive systems, as described in U.S. Pat. No. 5,244,996.
Although useful in these and other applications, industry is constantly seeking to broaden and improve the applicability of .alpha.-olefin/vinyl or vinylidene interpolymer containing materials. To perform well in certain applications, it may be desirable to modify the properties of interpolymer-containing materials. For example, it is desired to extend the range of temperatures in which these interpolymers may be utilized. Other properties which are desirable to modify include processing and/or fabrication characteristics, glass transition temperatures (T.sub.g), modulus, hardness, viscosity, elongation, fire retardation, density, melt index (MI), tensile strength, compatibility with other materials in composition, and virtually any other property. Industry is also interested in achieving modifications of various physical parameters without detrimentally effecting other preferred polymer properties. Any advantageous modifications are especially useful if achieved in a cost-effective manner.
Development of interpolymers that can be highly filled is sought, in particular, for sound management applications. Prior attempts to formulate compositions particularly useful for sound management applications use highly filled ethylene-vinylacetate copolymers (EVA). These highly filled blends are deficient, however, in that they possess physical properties that restrict available fabrication techniques. For example, EVA-based formulations must be kept at processing temperatures below 185.degree. C. to prevent degradation.
Thus, there is a need for other materials without these restrictions. For example, there is a need for materials based on .alpha.-olefin/vinyl or vinyledene monomer substantially random interpolymers with superior performance characteristics to unmodified polymers and the prior art. In particular, there is a great need for economic forms of this class of materials, which are highly processable.